This proposal is for the continuation of a program to develop an instrument for the accurate recordings of life events (Inventory of Discrete Events, IDEs), for use in the Collaborative Studies of the Psychobiology of the Depressive Illnesses. It would also be of use in general studies designed to explore the relationship between life events and illness onset. Further development of the IDEs and the establishment of its reliability and validity are planned. Three hundred psychiatric patients and 100 non-psychiatric subjects ("controls") will be interviewed together with a co-informant. Third parties will be queried so that the validity of the responses to the IDEs can be established. A self-administered form of the IDEs will be developed and tested. The response to the IDEs will be compared with measures of psychopathology to see whether the degree of symptomatology affects responses to this new instrument.